What the ATV630D18N4 is and what it drives
The ATV630D18N4 is a variable speed drive from Schneider Electric's Altivar Process ATV600 series, built for process and utility applications like pumps, fans, and compressors. It drives both asynchronous and synchronous motors at up to 18.5 kW in normal duty or 15 kW in heavy duty, with a nominal output current of 39.2 A from a 380…480 V supply. This is the standard version — no conformal coating or extended temperature range. The IP21 / UL Type 1 enclosure means it's meant for indoor panel mounting, not washdown environments.
Ratings that set the breaker and cable size
Line current at 380 V normal duty is 33.4 A; at 480 V heavy duty it drops to 24.4 A. The continuous output current at 4 kHz carrier is 39.2 A for normal duty and 31.7 A for heavy duty — that's the number for sizing the motor feeder and upstream protection. The integrated EMC filter handles 50 m of motor cable at C2 limits and 150 m at C3, per IEC 61800-3. That saves the cost of an external filter for most installations. For longer runs, you'll need an output reactor. Total harmonic current distortion stays below 48 % at 80…100 % load, meeting IEC 61000-3-12 — no need for a line reactor on most utility feeds.
Built-in safety and control I/O
That eliminates the need for an external safety relay on the power stage — wire the STO inputs directly to the safety circuit. Eight discrete inputs are on board, with DI7 and DI8 programmable as pulse inputs up to 30 kHz for encoder or flowmeter feedback. The adjustable PID regulator handles closed-loop process control without an external controller. Communication ports include Modbus TCP, Modbus serial, and Ethernet as standard. Slot A accepts optional Profibus DP V1, PROFINET, DeviceNet, CANopen, or Ethernet Powerlink modules — fieldbus selection is done at ordering.
Mounting and environment constraints
Operating altitude derating starts at 1000 m: 1 % current reduction per 100 m above that. At 4800 m the drive still runs but at roughly 62 % of rated output — plan accordingly for high-altitude sites. Shock rated at 15 gn for 11 ms, vibration at 1.5 mm pp up to 13 Hz and 1 gn from 13…200 Hz — tough enough for most industrial machinery but not for direct mounting on a vibrating pump skid without isolation mounts.